Photorespiration: Studies with Whole Tissues

Abstract

The discovery of the process of photorespiration, the rapid evolution of CO2 in light of photosynthetic tissues, was long delayed, and the history of the failure of scientists to recognise the importance of this process provides an example that may be instructive. Rabinowitch (1945) in his comprehensive treatise on photosynthesis considered the possibility that an acceleration of dark respiration might occur in photosynthetic tissues in the light. However, he and others failed to consider that photorespiration may be derived from biochemical reactions completely different from those of dark respiration and might possess distinctly different properties. The experiments were frequently carried out at high concentrations of CO2, low levels of O2, weak light, and low temperatures, conditions which inhibit photorespiration and interfere with its detection.